U0112

Lost Communication With Battery Energy Control Module B

Communication network (CAN bus) Generic OBD-II High

What it means

U0112 means another module has lost communication with battery energy control module B, which manages battery and energy flow. On a hybrid or EV this module is central to propulsion and charging, so losing it can disable the electric drive or cause a no-start; on conventional stop-start systems the effects are milder. It usually traces to wiring, connector, power/ground, or bus faults at the module, or a failed module.

High

Can I keep driving? Depends on the vehicle — on a hybrid or EV the battery energy module is core to propulsion, so losing it can disable the hybrid/electric drive or cause a no-start; on conventional stop-start systems the effects are milder. Treat as urgent on an electrified vehicle.

Common symptoms

What you'll notice

Hybrid/EV system warning or 'service' message on
Reduced hybrid/electric drive, no propulsion, or a no-start on electrified vehicles
Charging or battery-management faults, including stop-start not working
Other modules logging lost-communication codes for the battery energy module

Common causes

Most likely first

Wiring or connector fault at the battery energy control module B (opens, corrosion, damage)Likely
Loss of power or ground to the moduleCommon
CAN bus wiring fault on the branch feeding the moduleCommon
High-voltage or battery-system interlock issue taking the module offlineLess often
Failed battery energy control moduleLess often

How to diagnose & fix

Work through it in order

Scan all modules to confirm the battery energy module B is the one offline and note related battery codes.
On a hybrid/EV, observe high-voltage safety procedures before working near the battery system.
Check power, ground, and the CAN bus wiring at the module connector.
Inspect for corrosion, damage, or water intrusion at the module and connectors.
If wiring and supply are good, the module may be failed — diagnose and replace/program per the manufacturer procedure, then re-test.

FAQ

Quick answers

Is it safe to drive with U0112?+

On a hybrid or EV, be very cautious — the battery energy module manages the high-voltage system, and losing it can cut propulsion or prevent starting. Have it diagnosed before driving an electrified vehicle.

Can I just clear U0112?+

It clears, but returns if there's a wiring, power, or module fault. Battery-system faults on electrified vehicles should be properly diagnosed, not just cleared.

Related codes

Often seen with U0112

U0100Lost Communication With ECM/PCM "A"U0110Lost Communication With Drive Motor Contro U0111Lost Communication With Battery Energy Con U0113Lost Communication With Emissions Critical

Read & clear U0112 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

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✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX